In 2017, the American Cancer Society estimates that 161,360 men will be diagnosed with, and 26,730 will die from, prostate cancer.

An estimated 92% of these men are diagnosed with low-grade, localized prostate cancer, with many seeking to implement dietary and lifestyle changes to prevent prostate cancer recurrence or progression.

The authors of the paper, published in The Prostate journal, noted dairy products have been examined in relation to prostate cancer for several decades, and data generally suggest dairy products are associated with an increased risk of being diagnosed with prostate cancer among healthy men, although results have been inconsistent.

They also state that less is known about dairy products’ influence on prostate cancer after diagnosis.

Obesity increases risk

In this study of 1,334 men initially diagnosed with non-metastatic prostate cancer, results showed men who consumed more than four servings per week of whole milk had a 73% increased risk of recurrence compared to men who consumed fewer than three servings per month.

Also, among very overweight and obese men (body mass index greater than or equal to 27kg/m2), more than four servings a week compared to three or fewer servings per month of whole milk was associated with a threefold higher risk of recurrence.

Previous work

The study follows the researchers previous work, when they studied 3,918 men in the Health Professionals Follow-up Study (HPFS).

In that research, those who consumed whole milk more than four times per week after prostate cancer diagnosis had a twofold increased risk of prostate cancer-specific mortality, and a 51% increased risk of prostate cancer recurrence compared to men consuming whole milk fewer than three times per month.

The group also previously reported that among the 926 men in the Physicians’ Health Study, those who consumed more than three servings per day of dairy products after prostate cancer diagnosis had a 2.4-fold increased risk of prostate cancer-specific mortality compared to men having less than one serving per day.

Recent Swedish study

They also point to a recent Swedish study, which showed that in 230 men diagnosed with localized prostate cancer, men drinking more than three servings per day of high-fat milk had a 6.1-fold increase of prostate-cancer mortality compared to men consuming less than one serving per day.